Oil-cooled carbon seal

Abstract

A seal system has: a first member; a seal carried by the first member and having a seal face; and a second member rotatable relative to the first member about an axis. The second member has: a seat on a first piece of the second member, the seat having a seat face in sliding sealing engagement with the seal face; and a radially outwardly closed collection channel for collecting centrifuged oil; a second piece encircling and attached to the first piece and having a circumferential array of apertures; and cooperating with the first piece to define a plenum; and a flowpath from the collection channel passing radially outward axially spaced from the seat face to cool the seat face and passing axially away from the seat face in the plenum.

What is claimed is: 
     
       1. A seal system comprising:
 a first member; 
 a seal carried by the first member and having a seal face; and 
 a second member rotatable relative to the first member about an axis and having:
 a seat on a first piece of the second member, the seat having a seat face in sliding sealing engagement with the seal face; and 
 a radially outwardly closed collection channel for collecting centrifuged oil; 
 a second piece encircling and attached to the first piece and:
 having a circumferential array of apertures; and 
 cooperating with the first piece to define a plenum; and 
 
 a flowpath from the collection channel passing radially outward axially spaced from the seat face to cool the seat face and passing axially away from the seat face in the plenum. 
 
 
     
     
       2. The seal system of  claim 1  wherein:
 the flowpath passes through a plurality of passageway legs in the first piece. 
 
     
     
       3. The seal system of  claim 2  wherein:
 the flowpath passes from the passageway legs in the first piece through an annular channel in the first piece and to the plenum. 
 
     
     
       4. The seal system of  claim 2  wherein:
 the passageway legs are first passageway legs, the flowpath passing from the first passageway legs and through respective associated second passageway legs in the first piece and to the plenum. 
 
     
     
       5. The seal system of  claim 4  wherein:
 the second passageway legs have respective spiral surface enhancements. 
 
     
     
       6. The seal system of  claim 4  wherein:
 the second passageway legs are threaded. 
 
     
     
       7. The seal system of  claim 1  wherein:
 the seal is a carbon seal. 
 
     
     
       8. The seal system of  claim 1  wherein:
 the seat is steel; and 
 the seat and seal are full annular. 
 
     
     
       9. A gas turbine engine including the seal system of  claim 1  wherein:
 the second member is a shaft. 
 
     
     
       10. The gas turbine engine of  claim 9  wherein the seal system further comprises:
 an oil source positioned to introduce oil to the collection channel. 
 
     
     
       11. A method for using the seal system of  claim 1 , the method comprising:
 relatively rotating the second member to the first member about the axis; and 
 the rotation centrifugally driving a flow of oil along the flowpath to cool the seat face. 
 
     
     
       12. The method of  claim 11  further comprising:
 spraying the oil from a nozzle. 
 
     
     
       13. The method of  claim 11  further comprising:
 the flow accumulating oil in the collection channel; and 
 the flow passing from the collection channel through a plurality of passageway legs in the first piece. 
 
     
     
       14. The method of  claim 13  further comprising:
 the flow passing to the plenum; and 
 the flow discharging from the plenum through the apertures. 
 
     
     
       15. The method of  claim 14  further comprising: the flow passing through a cooling channel between the plurality of passageway legs and the plenum to cool the seat face. 
     
     
       16. The method of  claim 11  further comprising: the flow cooling the seat face while flowing through a cooling channel. 
     
     
       17. The gas turbine engine of  claim 9  further comprising:
 a plurality of passageway legs in the first piece having respective ends at the collection channel. 
 
     
     
       18. The gas turbine engine of  claim 17  wherein:
 the plurality of said passageway legs in the first piece is  20  to  80 ; and 
 the plurality of said apertures is  20  to  80 . 
 
     
     
       19. The gas turbine engine of  claim 9  wherein:
 the passing of the flowpath from the collection channel passing radially outward axially spaced from the seat face to cool the seat face is through a cooling channel having an outer diameter opening to the plenum; and 
 the plurality of apertures are axially offset from the cooling channel outer diameter opening by 0.10 inch to 0.50 inch. 
 
     
     
       20. The seal system of  claim 2  wherein:
 the plurality of said passageway legs in the first piece is 20 to 80; and 
 the plurality of said apertures is 20 to 80.